Excavation system and method

ABSTRACT

An excavation system has a soil-agitation arrangement including an agitator operable to disturb soil to facilitate removal of disturbed soil from the ground. Also included is a vacuum arrangement operable to remove the disturbed soil from the ground, and a sensor arrangement including at least one sensor configured to detect a presence of at least one type of buried infrastructure in the ground. A shroud arrangement including a shroud disposed over at least a portion of the agitator and may be movable relative to the agitator to selectively cover and uncover at least a portion of the agitator.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. provisional application No. 62/458,774 filed Feb. 14, 2017, which is hereby incorporated by reference herein.

TECHNICAL FIELD

The present disclosure relates to an excavation system and method.

BACKGROUND

Utility companies and associated service providers often need to access buried infrastructure such as gas mains, electrical service lines, and water and sewer systems. In some locations—for example, in highly-populated urban centers—buried utility infrastructure is so closely packed together as to make it a challenge to excavate the ground to access a particular infrastructure system, while not damaging surrounding systems. It would be desirable, therefore, to have a system and method for excavation that provided access to buried infrastructure assets, while not adversely impacting other, nearby infrastructure systems.

SUMMARY

At least some embodiments described herein may include an excavation system having a soil-agitation arrangement including an agitator operable to disturb soil to facilitate removal of the disturbed soil from the ground. A vacuum arrangement may be operable to remove the disturbed soil from the ground, and a sensor arrangement including at least one sensor may be configured to detect a presence of at least one type of buried infrastructure or obstructions—including rocks, debris, buried objects, etc.—in the ground. A shroud arrangement including a shroud disposed over at least a portion of the agitator may be movable relative to the agitator to selectively cover and uncover at least a portion of the agitator.

At least some embodiments described herein may include a control system including at least one controller and configured to control the operation of at least the soil-agitation arrangement and the vacuum arrangement. The shroud arrangement may be configured to communicate with the control system to provide information related to a reaction force experienced by the shroud. A sensor arrangement may be configured to communicate with the control system to provide information related to the presence of the at least one type of buried infrastructure and the status of the excavation system, including the detection of vacuum levels.

At least some embodiments described herein may include an excavation system having a soil-agitation arrangement including an agitator with a cutting portion operable to disturb soil to facilitate removal of the disturbed soil from the ground. The soil-agitation arrangement may have a cover portion at least partially surrounding the cutting portion of the agitator when the soil-agitation arrangement operates. The excavation system may further have a vacuum arrangement operable to remove the disturbed soil from the ground.

At least some embodiments described herein may include an excavation system having a soil-agitation arrangement including an agitator operable to disturb soil to facilitate removal of disturbed soil from the ground. The soil-agitation arrangement may also have a force-sensitive portion configured such that damage to a buried infrastructure during operation of the agitator is inhibited. The excavation system may also have a vacuum arrangement operable to remove the disturbed soil from the ground.

At least some embodiments described herein may include an excavation system that includes a soil-agitation arrangement including an agitator operable to disturb soil to facilitate removal of disturbed soil from the ground. The soil-agitation arrangement may further including a flexibly movable portion configured such that damage to a buried infrastructure during operation of the agitator is inhibited. The excavation system may also include a vacuum arrangement operable to remove the disturbed soil from the ground.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a perspective view of an excavation system in accordance with embodiments described herein;

FIG. 2 shows an exploded view of the excavation system shown in FIG. 1;

FIG. 3 shows a portion of an excavation system in accordance with embodiments described herein;

FIG. 4 shows a portion of an excavation system in accordance with other embodiments described herein;

FIG. 5 shows an excavation system in accordance with embodiments described herein, including a mobile robotic unit;

FIG. 6 shows the excavation system from FIG. 5 accessing buried infrastructure;

FIG. 7A shows a bladder arrangement forming a portion of an excavation system in accordance with embodiments described herein;

FIG. 7B shows the bladder arrangement in an inflated state;

FIG. 8 shows a bladder arrangement forming a portion of an excavation system in accordance with embodiments described herein, wherein the bladder arrangement includes an outer sleeve;

FIG. 9 shows a portion of an excavation system in accordance with embodiments described herein, including a vacuum hood and a flexible auger; and

FIG. 10 shows an excavation system in accordance with embodiments described herein, including a backhoe.

DETAILED DESCRIPTION

As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention that may be embodied in various and alternative forms. The figures are not necessarily to scale; some features may be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present invention.

FIG. 1 shows an excavation system 10 in accordance with embodiments described herein. The excavation system 10 includes a drive motor assembly 12—which, in this embodiment, includes a drill motor 13—a support structure 14 for the drill motor 13, a drive tube assembly 16, and a cover portion or shroud 18. As shown in FIG. 1, a driving sprocket 20 is configured to be rotated by the drill motor 13. Although not visible in FIG. 1, it is understood that a chain or other drive-belt member connects the driving sprocket 20 with a driven sprocket 22 that is part of the drive tube assembly 16. Illustrated partly schematically in FIG. 1 is a sensor arrangement 23, forming at least a part of a sensor system, and which includes one or more sensors configured to detect the presence of buried infrastructure. For example, the sensor arrangement 23 may include a Hall effect sensor to detect the presence of magnetic flux, indicating a buried electrical line. Alternatively, or in conjunction with a Hall effect sensor, the sensor arrangement 23 may include an inductive sensor to detect the presence of ferrous metals, such as might be used in a wall of a gas main. As indicated by the dashed arrow, the sensor arrangement 23 is configured to output signals and provide information related to the buried infrastructure to a control system.

FIG. 2 shows an exploded view of the excavation system 10 with many of the fasteners and other small components removed for clarity. In addition to the various components described in conjunction with FIG. 1, the excavation system 10 includes a drill motor clamp 24 and a drill motor support 26. An adapter 28 is secured on the drill motor 13, for example, with a Morse taper fit. A drive shaft 30 is secured in the adapter 28 and is connected to the driving sprocket 20 with a shaft key 32. The motor drive assembly 12 further includes top and bottom support plates 34, 36, each of which has a respective bearing 38, 40 to support and facilitate rotation of the adapter 28 and the driving sprocket 20. Although the motor drive assembly 12 is illustrated and described in FIGS. 1 and 2 as being positioned outside of the drive tube assembly 16, and connected to it through a chain-drive mechanism, other embodiments may include different types of power transfer arrangements, and may include a drive motor assembly inside or otherwise in-line with the drive tube assembly 16.

Also shown in FIG. 2 is a bucket base assembly 42 and a top drive plate 44, which are spaced apart from each other by spacers 46, 48, 50, 52—see also FIG. 1. A vacuum coupling tube 54 and flange 56, as well as a top vacuum plate 58 and bushing 60 are also part of the excavation system 10. The drive tube assembly 16 includes a drive tube 62 and a support tube 64 configured to be disposed on the outside of the drive tube 62. An agitator, which in this embodiment is an auger 66, is configured to be attached to the drive tube 62; a coupling 68 and O-ring 70 help facilitate this attachment. The auger 66 includes a cutting portion 67, which in this embodiment includes rotary blades. The drive motor assembly 12 and drive tube assembly 16 make up a part of a soil-agitation arrangement that includes the auger 66, and is configured to disturb the soil after the asphalt or concrete top layer has been removed so that the soil can be removed more easily.

Although the agitator in the embodiment illustrated in FIG. 2 is an auger, other embodiments, some of which are described and illustrated herein, contemplate the use of different agitators—e.g., different types of blade arrangements, tines, or cups, just to name a few. The embodiment illustrated in FIGS. 1 and 2 uses a chain or belt to transfer torque from the motor 13 to the drive tube 62; however, in other embodiments a direct-drive system may be used. For example, a motor may drive the drive tube assembly 16 or the auger 66 directly, without the use of a chain or belt. Gears, clutches, and other mechanical systems may be used to transfer torque from a motor to a driven component such as the drive tube assembly 16 or auger 66. Although the sensor arrangement 23 may be attached to a bottom surface of the top drive plate 44, in other embodiments, a sensor arrangement may be mounted or embedded in the bottom face or the sides of a shroud, such as the shroud 18, or a vertical section of the tubing, such as the drive tube 62 or the support tube 64.

As shown in FIG. 2, the auger 66 extends beyond an end 72 of the shroud 18. In contrast, the shroud 18 completely covers the auger 66 as shown in FIG. 1; this is because the shroud 18 is flexibly movable with respect to the auger 66, and in particular, in the illustrated embodiment, it is movable up and down the support tube 64. This configuration helps to ensure that the auger 66 will not inadvertently contact buried infrastructure while it is in the process of disturbing the soil for removal. As described in more detail below, a cover portion, such as the shroud 18, may be attached to a support tube or other portion of an excavation system with a suspension system that communicates with a control system to provide feedback regarding resistance—i.e., a reaction force on the shroud 18—provided by the ground or objects in the ground during the excavation.

In at least some embodiments, the disturbed soil will be removed with a vacuum process to clear the area of interest to provide access to the buried infrastructure. In the embodiment illustrated in FIGS. 1 and 2, a vacuum arrangement includes the drive tube 62, which is generally hollow, and the vacuum coupling tube 54, which is configured to receive a hose or other conduit connected to a vacuum—see FIG. 1 indicating a remotely-located vacuum. In at least some embodiments, the vacuum may be disposed on a truck or mobile platform that is also configured to store the soil and other debris from the ground so that it can be reintroduced into the excavation after the work is done, or moved to an off-site location.

FIG. 3 shows a portion of an excavation system 74 in accordance with embodiments described herein. In particular, FIG. 3 shows a portion of a support structure or support tube 76 disposed on the outside of an inner tube 78, which may be a drive tube similar to the drive tube 62, or it may just provide a conduit for soil and other debris to be vacuumed away from the excavation. In such an embodiment, a drive mechanism may be disposed at least partially within the inner tube 78 to drive an auger or other agitator 79 at least partially covered by a cover or shroud 80. In the embodiment shown in FIG. 3, the shroud 80 is attached to the support tube 76 via a hinge 82 and a linear actuator, which in this embodiment is a linear actuating cylinder 84. The cylinder 84 may, for example, be an electrical, pneumatic, or hydraulic actuator system. As shown in FIG. 3, the cylinder 84 is connected to a control system shown schematically at 86. The control system 86 may also receive feedback from a sensor arrangement, such as the sensor arrangement 23 shown in FIG. 1.

The control system 86 may receive any number of inputs and be preprogrammed with various logic algorithms, including artificial intelligence architecture, to make decisions on an excavation being performed by the excavation system 74. The control system 86 may then output signals to control various aspects of the excavation system 74, such as how much force to apply to the soil, and what angle to tilt the shroud 80 as the excavation is proceeding. Because the shroud 80 tilts at an angle relative to the support tube 76, excavation can proceed at various angles without having to manipulate the entire excavation system 74. This may further help to protect buried infrastructure as the agitator 79 is operated because the shroud 80 can be angled with an orientation to protect the infrastructure from the action of the agitator 79.

The shroud 80 shown in FIG. 3 has an end 87 with a flat edge, similar to the end 72 of the shroud 18 shown in FIGS. 1 and 2. Alternatively, an end of the shroud may be configured with a scalloped edge 89 such as shown by the dashed line in FIG. 3. Having a shroud with a scalloped or other non-flat edge may avoid having the shroud seal to the ground while a high-strength vacuum is being pulled. The irregularities in an edge, such as the edge 89, may also enable better penetration into hard-packed soil. Although the end 72 of the shroud 18 is shown with a flat edge, it is understood that it and any other embodiments described herein may also have a non-flat edge on a shroud.

FIG. 4 shows a portion of an excavation system 88 that includes a support structure including a support tube 90 and a cover portion or shroud 92, which at least partially surrounds a cutting portion of an agitator 94. The agitator 94 may have blades such as the auger 66, or the cutting portion may include teeth or other cutters, such as the cutters 124 shown in FIGS. 7A and 7B and described below. The shroud 92 is connected to the support tube 90 via cylinders 96, 98. The cylinders 96, 98 may provide a rigid attachment between the cover portion 92 and the support structure 90. In such a case, it may be convenient to have a bottom edge of the cover portion 92 be scalloped, such as shown on the cover portion 80 in FIG. 3. In at least one embodiment, such as the embodiment shown in FIG. 4, the cover portion 92 may cover all of the cutting portion of an agitator, such as the agitator 94. In doing so, the cover portion 92 protects an underground infrastructure, such as a pipeline.

Alternatively, the cylinders 96, 98 may be pressure-sensitive devices that communicate with a control system 100, which itself may communicate with a sensor system, such as by communicating with the sensor arrangement 23 shown in FIG. 1. In such an embodiment, the cylinders 96, 98 provide a suspension for the shroud 92, and provide feedback information to the control system 100 related to a reaction force experienced by the shroud 92 as it is contacting an object, and in this way the sensor arrangement 23 may facilitate movement of the cover portion 92. In at least some embodiments, when the reaction force is relatively small, the cylinders 96, 98 may be controlled by the control system 100 to allow the shroud 92 to move upward to expose and position the cutting portion of the agitator 94. Conversely, where the reaction force is greater—perhaps indicating buried infrastructure—the control system 100 may take any number of actions, including keeping the shroud 92 over the agitator 94, changing a direction of the excavation away from the object of resistance, or even discontinuing operation of the agitator 94.

A method in accordance with embodiments described herein may include some or all of the following steps, which reference the illustrated systems described above, and which may be performed in the order indicated or in a different order depending on the particular application. After a top layer of asphalt or concrete is removed from an excavation site, the excavation system 10 may be moved into position and connected to a control system and vacuum if the connections have not already been made. The sensor system 23 may provide feedback immediately to the control system to indicate the presence of buried infrastructure. Absent any immediate concerns of contacting infrastructure, the drive motor assembly 12 may be operated to drive the auger 66 or other agitator. Depending on feedback from the sensor arrangement 23, and from other sensors—see the suspension arrangement comprising pressure-sensitive cylinders 96, 98 in FIG. 4—the shroud 18 may be moved away from the auger 66 to allow it to disturb the soil as a vacuum pulls the soil up through the drive tube 62, the vacuum coupling tube 54, and ultimately to a vacuum system for collection. Alternately, a shroud, such as the shroud 18, does not move out of the way, but rather contacts the object first and provides protection from the auger. If the shroud is configured with a tilt mechanism such as shown in FIG. 3, it may be oriented to avoid contact between the auger 66 and buried infrastructure, and in the case of feedback received from a suspension system such as shown in FIG. 4, the auger 66 may be moved away from detected infrastructure or even turned off.

FIG. 5 shows an excavation system 102 in accordance with embodiments described herein. The excavation system 102 includes a mobile robotic unit 104 having an articulating arm 106. As shown in FIG. 5, the articulating arm 106 has a sensor array 108 attached to it. At this stage of the process, the sensor array 108 is locating and identifying underground infrastructure indicated by the conduits 110, 112, 114. Once the particular infrastructure is located and identified, a portion of the pavement 116 will be removed so that soil and other material can be removed from the ground using a system, such as the system 10 described above. FIG. 6 shows the mobile robotic unit having an excavator 118 attached to it. The excavator 118 includes a soil agitator and vacuum arrangement similar to that which was described above in conjunction with the excavation system 10. FIGS. 5 and 6 show how excavation systems, such as the excavation system 10, can be used in conjunction with mobile robotic units, which may be deployed from a large truck. The truck may then be the point of operation for a technician and contain all of the control systems and monitors required to use the excavation system and perform the steps described above.

FIG. 7A shows a bladder arrangement 120 forming a portion of an excavation system in accordance with embodiments described herein. More specifically, the bladder arrangement 120 is part of a soil-agitation arrangement that may be used in accordance with excavation systems described above. The bladder arrangement 120 includes an inflatable bladder 122 having numerous cutters 124 disposed on an outside thereof—not all of the cutters 124 are labeled in the drawing figure. The bladder 122 may be sealed at one end 126 and have another end 128 open to allow air to enter to inflate the bladder 122 as shown in FIG. 7B. Because the bladder 122 is flexible, and its stiffness can be adjusted based on the amount of internal pressure of the air inside of it, the bladder arrangement 120 acts as a compliant auger that can agitate the soil, but which will yield to a rigid structure such as buried infrastructure. FIG. 8 shows the bladder arrangement 120 having a sleeve 130 disposed over a portion of the outside surface 132 of the bladder 122. The sleeve 130 may be made from a flexible material that is resistant to wear and protects the bladder 122 from puncture. For example, the sleeve 130 may be made from a steel mesh material, which still allows the bladder 122 to inflate, but protects the outside surface 132.

FIG. 9 shows a portion of an excavation system 134 in accordance with embodiments described herein. The excavation system 134 includes a vacuum arrangement 135 having a vacuum tube 136 and a vacuum hood 138, which may be connected to a vacuum as described above. A portion of a support structure 140 is also shown, and may extend for some or all of length of the vacuum tube 136. The excavation system 134 also includes a soil-agitation arrangement 142, which includes an agitator configured as an elongate member, which in this embodiment is a flexible elongate member or shaft 144, having a cutting portion in the form of a number of cutting elements 146 disposed on its outside surface 148. As shown in FIG. 9, the flexible shaft 144 has conformed to a curved outside surface of a pipeline 150. Once having moved downward through the soil until it reaches the pipeline 150, the soil-agitation arrangement 142 can be moved along a length of the pipeline 150 to clear away soil and other ground material in very close proximity to an outside surface of the pipeline. And because the shaft 144 is flexible, the soil-agitation arrangement 142 can operate in such a way that during contact between the pipeline 150 and the soil-agitation arrangement 142, damage to the pipeline 150 is inhibited—i.e., completely eliminated or significantly reduced.

FIG. 10 shows an excavation system 152 in accordance with embodiments described herein. The excavation system 152 includes a small backhoe 154 having an articulating arm 156. Attached to the arm 156 is a soil-agitation arrangement 158 that includes a motor assembly 160 mounted on a support structure 162. The soil-agitation arrangement 158 also includes a tube assembly 164, which, similar to the tube assembly 16, includes a support tube 166 and may include a drive tube or other drive component positioned within the support tube 166. A shroud 168 has been removed to reveal a mechanical agitator 170, which may be, for example, an auger such as described above in conjunction with FIGS. 1 and 2. The backhoe 154 also carries a vacuum arrangement 172 that is operable to remove soil disturbed by the agitator 170, which is then sucked through a tube 174 and collected in a tank 176. Also shown in FIG. 10 is a display screen 178, which may be, for example, a touchscreen that provides inputs to a control system, or it may be an output device only that provides information regarding sensor feedback from a control system to the operator. Thus, the excavation system 152 is mobile and self-contained for ease of access and operability at different locations.

While exemplary embodiments are described above, it is not intended that these embodiments describe all possible forms of the invention. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention. Additionally, the features of various implementing embodiments may be combined to form further embodiments of the invention. 

What is claimed is:
 1. An excavation system, comprising: a soil-agitation arrangement including an agitator with a cutting portion operable to disturb soil to facilitate removal of disturbed soil from the ground, the soil-agitation arrangement having a cover portion at least partially surrounding the cutting portion of the agitator when the soil-agitation arrangement operates; and a vacuum arrangement operable to remove the disturbed soil from the ground.
 2. The excavation system of claim 1, wherein the soil-agitation arrangement includes a flexibly movable portion configured to inhibit damage to a buried infrastructure when the soil-agitation arrangement operates.
 3. The excavation system of claim 2, wherein the flexibly movable portion includes the cover portion.
 4. The excavation system of claim 3, wherein the cover portion is movable relative to the agitator to selectively cover and uncover at least a portion of the cutting portion of the agitator.
 5. The excavation system of claim 4, further comprising a sensor system including a sensor arrangement configured to receive input related to a reaction force on the cover portion when the cover portion contacts an object, and further configured to facilitate movement of the cover portion to selectively cover and uncover at least a portion of the agitator based at least in part on the reaction force.
 6. The excavation system of claim 5, wherein the soil-agitation arrangement further includes a support structure having at least one linear actuator attached to the cover portion and operable to move the cover portion relative to the agitator.
 7. The excavation system of claim 6, wherein the at least one linear actuator is configured to provide feedback to the sensor arrangement related to the reaction force.
 8. The excavation system of claim 7, wherein the sensor arrangement is configured to provide output to facilitate operation of the at least one linear actuator based at least in part on the reaction force.
 9. The excavation system of claim 2, wherein the flexibly movable portion includes the agitator.
 10. The excavation system of claim 9, wherein the agitator is configured as an elongate member supported on at least one end, and deflectable on contact with the buried infrastructure such that damage to the buried infrastructure from contact with the agitator is inhibited.
 11. An excavation system, comprising: a soil-agitation arrangement including an agitator operable to disturb soil to facilitate removal of disturbed soil from the ground, and further including a force-sensitive portion configured such that damage to a buried infrastructure during operation of the agitator is inhibited; and a vacuum arrangement operable to remove the disturbed soil from the ground.
 12. The excavation system of claim 11, wherein the force-sensitive portion includes the agitator.
 13. The excavation system of claim 12, wherein the soil-agitation arrangement further includes a vacuum hood, and the agitator includes a flexible elongate member supported on the vacuum hood such that damage to a buried infrastructure is inhibited during contact between the buried infrastructure and the soil-agitation arrangement.
 14. The excavation system of claim 11, wherein the force-sensitive portion includes a shroud arrangement disposed at least partly over the agitator and being movable relative to the agitator to selectively cover and uncover at least a portion of the agitator.
 15. The excavation system of claim 14, further comprising a sensor system configured to process information related to a presence of the buried infrastructure, and wherein the shroud arrangement is configured to provide feedback to the sensor system related to a reaction force when the shroud arrangement contacts an object.
 16. The excavation system of claim 15, wherein the sensor system is configured to provide output to facilitate operation of the shroud arrangement based at least in part on the reaction force.
 17. An excavation system, comprising: a soil-agitation arrangement including an agitator operable to disturb soil to facilitate removal of disturbed soil from the ground, and further including a flexibly movable portion configured such that damage to a buried infrastructure during operation of the agitator is inhibited; and a vacuum arrangement operable to remove the disturbed soil from the ground.
 18. The excavation system of claim 17, wherein the flexibly movable portion includes a shroud arrangement disposed at least partly over the agitator and being movable relative to the agitator to selectively cover and uncover at least a portion of the agitator.
 19. The excavation system of claim 18, further comprising a sensor system configured to receive input related to a reaction force on the shroud arrangement when the shroud arrangement contacts an object, and further configured to facilitate movement of the shroud arrangement to selectively cover and uncover at least a portion of the agitator based at least in part on the reaction force.
 20. The excavation system of claim 19, wherein the soil-agitation arrangement further includes a vacuum hood, and the flexibly movable portion includes the agitator, the agitator being configured as a flexible elongate member supported on the vacuum hood such that damage to the buried infrastructure is inhibited during contact between the buried infrastructure and the soil-agitation arrangement. 